This invention relates in general to treatment of exhaust gases or the like, and is an improvement over the electrical ignition devices for for treating exhausts as disclosed in my prior U.S. Pat. Nos. 3,902,854 and 4,163,772, respectively issued Sept. 2, 1975 and Aug. 7, 1979.
In the foregoing type of electrical ignition devices, the exhaust gases being treated are conducted through a chamber mixed with moisture to control the electrical conductivity of the exhaust. A spark plug in the chamber intermittently ignites the moisture laden exhaust mixture by means of arcs produced across the gap between electrodes by peak voltage output of a transformer or ignition coil device powered from a D.C. source of voltage. According to my earlier patent, peak voltages are produced by timed operation of an interrupter switch through which the voltage source is connected across the primary winding of the transformer device. According to my later patent, the interrupter switch is replaced by connection of the primary winding to a current control terminal exposed to the moisture laden mixture in the grounded chamber through which voltage fluctuation across the primary winding is controlled by the conductivity of the exhaust mixture.